using Evergreen.Health.Application.Health.Devices.Environment;
using Evergreen.Health.Application.Health.Entities;
using Evergreen.Health.Application.Health.Integrations.HomeAssistant;
using Evergreen.Health.Application.Health.Models;
using Evergreen.Health.Application.Health.Policies;
using Microsoft.Extensions.Options;

namespace Evergreen.Health.Application.Health.Services;

/// <summary>组合独立的 BMI 和室温策略，不负责发送家具控制命令。</summary>
public sealed class MattressComfortService : ITransient
{
    private readonly IHomeAssistantGateway _gateway;
    private readonly IndoorEnvironmentReader _environment;
    private readonly HomeAssistantEntityOptions _entities;
    public MattressComfortService(IHomeAssistantGateway gateway, IndoorEnvironmentReader environment,
        IOptions<HomeAssistantOptions> options)
        => (_gateway, _environment, _entities) = (gateway, environment, options.Value.Entities);

    public async Task<MattressComfortOutput> GetAsync(HealthProfile? profile, CancellationToken cancellationToken = default)
    {
        IReadOnlyDictionary<string, HomeAssistantState> states;
        try
        {
            states = (await _gateway.GetStatesAsync(cancellationToken)).GroupBy(state => state.EntityId, StringComparer.OrdinalIgnoreCase)
                .ToDictionary(group => group.Key, group => group.Last(), StringComparer.OrdinalIgnoreCase);
        }
        catch (Exception exception) when (exception is not OperationCanceledException)
        {
            states = new Dictionary<string, HomeAssistantState>();
        }
        return Get(profile, states);
    }

    public MattressComfortOutput Get(HealthProfile? profile, IReadOnlyDictionary<string, HomeAssistantState> states)
    {
        var bmi = BmiFirmnessPolicy.Calculate(profile?.HeightCm, profile?.WeightKg);
        var firmness = BmiFirmnessPolicy.Firmness(bmi);
        var tcm = TcmConstitutionRules.Read(profile);
        var sample = _environment.Read(states);
        var advice = RoomTemperaturePolicy.Evaluate(sample, RecommendedRoomRange.ForConstitution(tcm.ConstitutionCode));
        advice.PendingIntegration = (advice.Mode is "heat" or "cool") && string.IsNullOrWhiteSpace(_entities.Climate);
        return new()
        {
            Bmi = bmi, Firmness = firmness, HeatingLevel = advice.Mode == "heat" ? 1 : 0,
            IndoorTemperatureCelsius = sample.Celsius, IndoorTemperatureAvailable = sample.Available,
            IndoorTemperatureObservedAt = sample.ObservedAt, HeatingReason = advice.Reason,
            WeatherReason = advice.Reason, // 旧客户端兼容字段，不再读取或依赖室外天气。
            ClimateAdvice = advice,
            FirmnessReason = firmness is null
                ? "健康档案尚无有效身高和体重，暂不自动调节软硬度"
                : $"按 BMI {bmi:0.0} 给出“{firmness}”演示起点，可在设备详情手动调整"
        };
    }

    public static void ApplyTo(PersonalizedSceneConfig config, MattressComfortOutput recommendation)
    {
        config.MattressHeatingLevel = recommendation.HeatingLevel;
        config.MattressLeftFirmness = recommendation.Firmness is null ? 0 : FirmnessLevel(recommendation.Firmness);
        config.MattressRightFirmness = config.MattressLeftFirmness;
        config.ClimateAdvice = recommendation.ClimateAdvice;
    }

    public static int FirmnessLevel(string firmness) => firmness switch
    {
        "最软" => 1, "很软" => 2, "稍软" => 3, "稍硬" => 4, "很硬" => 5, "最硬" => 6, _ => 0
    };

    public static string? FirmnessName(int level) => level switch
    {
        1 => "最软", 2 => "很软", 3 => "稍软", 4 => "稍硬", 5 => "很硬", 6 => "最硬", _ => null
    };
}